Selective chemical control of Amsinckia species in wheat

Abstract

The results of nine experiments in north-western Victoria investigating the chemical control of Amsinckia spp. growing in wheat are reported. The chemicals prometryne, linuron, bromoxynil, diuron, dicamba, and picloram were applied to seedling Amsinckia at an early stage of wheat growth. For comparison, treatments with 2,4-D applied at two stages of crop growth were included. Prometryne, linuron, and bromoxynil controlled Amsinckia in all trials, and wheat yields were increased. The early 2,4-D sprays controlled Amsinckia but reduced wheat yields. Later 2,4-D sprays, applied when wheat was fully tillered, caused some reduction in the density and dry weight of Amsinckia, but wheat yields were not increased.